MQTT without SparkPlug


I am using the latest Ignition Version.

I have configured MQTT, but it is using the Sparkplug configuration. I am looking forward to subscribing to a topic, not with the Sparkplug.

How can I create a topic?

Shashi Preetham.

I think you create a custom namespace to handle raw JSON.


what would be my URL now ?

If your subscription is correct, then the data should show up in your Ignition tag browser, something like ['MQTT Engine']MQTT/PLC/NewTag

I have done like this, But nothing showing up as of now:

You need something publishing data to that MQTT topic. If you're using a tool like MQTT explorer or MQTT.fx (I think that's what you're using there), you should be seeing data show up as long as some other device is publishing data to the topic. If you're not seeing it with those tools, Ignition won't see it either (unless you're using different usernames, in which case it could be a permissions issue).

Additionally, if you need to publish data to raw MQTT topics from Ignition using MQTT Engine or MQTT Transmission, you'll need to leverage Python script functions, as detailed in the Cirrus Link docs here and here (for MQTT Engine and Transmission, respectively).

In addition to @kcollins comment, if you need to publish raw MQTT don't use transmission, use engine. Transmission seems to create a new connection for every publish where engine uses its existing connection. Also, transmission seems to be a bit less reliable from one update to the next compared to engine in my experience.